﻿using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using Harvester.Forms;

/* Copyright (c) 2012-2013 CBaxter
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), 
 * to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, 
 * and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 
 * IN THE SOFTWARE. 
 */

namespace Harvester
{
    internal static class NativeMethods
    {
        private const Int64 ListViewGetHeader = 0x101F;

        [Serializable, StructLayout(LayoutKind.Sequential)]
        public struct Rectangle
        {
            public int Left;
            public int Top;
            public int Right;
            public int Bottom;
        }

        [DllImport("user32.dll")]
        private static extern IntPtr SendMessage(IntPtr hwnd, Int64 wMsg, Int64 wParam, Int64 lParam);

        [DllImport("user32.dll")]
        private static extern Boolean GetWindowRect(HandleRef hwnd, out Rectangle lpRect);
        
        public static Int32 GetHeaderHeight(ListView listView)
        {
            IntPtr hwnd = SendMessage(listView.Handle, ListViewGetHeader, 0, 0);
            Rectangle bounds;

            return GetWindowRect(new HandleRef(null, hwnd), out bounds)
                       ? bounds.Bottom - bounds.Top
                       : listView.Font.Height * 2;
        }
    }
}
